玉米淀粉小体低温冻融法制备及其微观结构特性研究  

Preparation and Microstructure Properties of Corn Starch Blocklets Obtained by Low-Temperature Freezing-Thawing Method

作　　者：余世锋 王海涛 郭鹏 汪陈洁 马成业[1] YU Shifeng;WANG Haitao;GUO Peng;WANG Chenjie;MA Chengye(School of Agricultural Engineering and Food Science,Shandong University of Technology,Zibo 255000,China)

机构地区：[1]山东理工大学农业工程与食品科学学院,山东淄博255000

出　　处：《食品科技》2022年第2期268-272,共5页Food Science and Technology

基　　金：山东理工大学博士科研启动项目(420054)。

摘　　要：以玉米淀粉颗粒为对象,采用低温冻融反复处理,通过微滤膜过滤分离,获得玉米淀粉小体,采用扫描电子显微镜、激光粒度仪、GPC和DSC测定了玉米淀粉小体微观结构、粒径特征、分子质量及热性质。实验结果表明:玉米淀粉颗粒具有低温脆性,低温冻融处理会导致玉米淀粉颗粒表面结构破坏,冻融次数增多,淀粉颗粒内外破裂明显,玉米淀粉小体易于解离;玉米淀粉小体为无规则形状,粒径为10~50 nm,多个玉米淀粉小体聚集形成葡萄状聚集体,玉米淀粉小体聚集体粒度大小在60~300 nm,平均粒度为180 nm;玉米淀粉小体重均分子质量Mw为1518 u,数均分子质量Mn为429 u,淀粉小体分子聚合度(DP)分布为3.54;玉米淀粉小体糊化过程分为2个过程,第一热转变阶段,糊化温度为(56.50±0.40)℃,峰值温度为(67.62±0.35)℃,焓变值为(1.57±0.22)J/g;第二热转变阶段,糊化温度为(94.53±0.32)℃,峰值温度为(99.60±0.40)℃,焓变值为(0.88±0.36)J/g。因此,通过控制低温冻融处理结合膜过滤可以获得淀粉小体,该研究结果可为纳米级淀粉小体制备及应用提供理论参考。Taking corn starch granules as the object,corn starch corpuscles were obtained by repeated treatment of low-temperature freezing and thawing and filtration and separation through microfiltration membrane.The microstructure,particle size characteristics,molecular weight and thermal properties of corn starch corpuscles were determined by scanning electron microscope,laser particle sizer,GPC and DSC.Results showed that corn starch had the low temperature brittleness,microstructure of corn starch was destroyed by low temperature freeze-thawing processing,and it was obviously broken and blocklets released when the freezing-thawing cycles increasing.The blocklets were irregular shape,the particles were of 10~50 nm,however,it was easy to assemble to a grape shape ranged of 60~300 nm,and the mean size of aggregation was 180 nm.The weight average molecular weight (Mw) of corn starch corpuscles was 1518 u,the number average molecular weight (Mn) was 429 u,and the molecular degree of polymerization (DP) distribution of starch blocklets was 3.54.The gelatinization process of corn starch blocklets could be divided into two processes.The first thermal transformation stage,gelatinization temperature was (56.50±0.40)℃,peak temperature was (67.62±0.35)℃,enthalpy change value was (1.57±0.22)J/g;In the second thermal transformation stage,the gelatinization temperature was (94.53±0.32)℃,the peak temperature was (99.60±0.40)℃,and the enthalpy value was (0.88±0.36)J/g.Therefore,we can prepare starch blocklets by low temperature freezing-thawing processing combined microfiltration membrane,which is useful and helpful for starch blocklets producing and application.

关 键 词：玉米淀粉 小体 解离 冻融 微观结构 纳米微粒 

分 类 号：TS235.1[轻工技术与工程—粮食、油脂及植物蛋白工程]